Excel 2003 doesn't calculate (not allways!)

[monsta]

hello,

we do have a strange problem with our excel 2003 (sp1) installation (Windows
XP SP2).

from time to time, excel doesn't calculate (in old sheets, also in new
ones). even if i type =1+1, the result is "0". when i save the file and open
it again, the result is "2".

F9 doesn't work. Calculation (Extras | Optionen) is automatic!

when i enter the formulabar and confirm the cell with the green (OK)
button, the formula is calculated...

strange thing, i know!

in 90% excel works fine and calculates, but sometimes, the described problem
appears...

can anyone help?

 

[Atlantis]

I am having the exact same problem and came to this website to see what the
problem is. I have a massive spreadsheet composed of vlookups,
concatenations and about 150 tabs. Some cells calculate and every now and
then we discover there are cells not calculating. Please let me know if you
figure out the solution by replying to this...